The arrests follow a $250,000 reward for information about the Australia Day death of Omega Ruston at Burleigh Heads in 2009.
The 32-year-old was allegedly shot in the stomach after he stopped following an incident on the highway.
Police believe two shots were fired from the rear passenger seat of a small maroon sedan, one of which fatally wounded the construction worker.
Queensland detectives travelled to Sydney on Tuesday seeking the extradition of three men arrested overnight as part of a joint investigation with NSW police.
A fourth man was arrested in Brisbane on Tuesday morning. The 45-year-old Gold Coast man allegedly "provided immediate assistance to the offenders after the murder had been committed," Queensland Police said.
He's due to face court in Brisbane on Wednesday, charged with accessory after the fact to murder, attempting to corrupt a witness, and perjury.
The first of the three men arrested across Sydney was allegedly trying to leave the country.
Hysam Hamdan, 43, was arrested by police as he tried to board a flight to Dubai, carrying $25,000 cash on Monday night.
A short time later, 37-year-old Paul Younan was arrested after police stopped a black Toyota HiLux he was driving on the M4 motorway at Huntingwood.
Both faced court on Tuesday and are due to be extradited to Brisbane on Thursday.
About 1.30am on Tuesday, police arrested a 39-year-old man who is also due to be extradited.
Detectives said the men have alleged links to Middle Eastern crime syndicates and outlaw motorcycle gangs.
The trio arrested in NSW were allegedly in the maroon sedan at the time of the murder, and police said the gun used to kill Mr Ruston had been used before.
"Police will allege that the firearm used in the shooting of Omega Ruston is an identical ballistic match to a firearm that was used in a drive-by style shooting at the West Sydney Ink tattoo parlour in late 2008," Qld police detective acting superintendent Chris Ahearn said.
The actual weapon has not been found.
Police searched the Parramatta River early last year after receiving information "concerning the location of the murder weapon".
"We haven't located anything in that part of the river that we undertook that search in at the time," Det Supt Ahearn said.
Det Supt Ahearn said at this stage the murder seems to be "an act of road rage ... that has ended in senseless violence and the loss of a young man's life".
The $250,000 reward remains in place "for information which leads to the apprehension and conviction of persons responsible for the murder of Omega," Det Supt Ahearn said.
He added there's "appropriate indemnity from prosecution" that can be recommended for accomplices "who first gives us information," provided they didn't pull the trigger.
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